string _filterName_needed="approved";
DataRow[] drr = dt.Select("status=' "+ _filterName_needed +" ' ");
for (int i = 0; i < drr.Length; i++)
{
dt.Rows.Remove(drr[i]);
}

string _filterName_needed="approved";
object obj = dt.Select("status=' "+_filterName_needed+" ' ");
DataRow drr = dt.Rows.Find(obj);
if (drr!=null)
{
drr.Delete();
}

for (int i = dt.Rows.Count - 1; i >= 0; i--)
    {
        if (dt.Rows[i]["status"].ToString() == "approved")
            {
                dt.Rows[i].Delete();
            }
    }